               (and (sequential? obj1) (sequential? obj2)) :seq-seq)))
 
 (defmethod check-collision :map-map [obj1 obj2]
-  (if (collide? obj1 obj2)
+  (if (and (:collidable? obj1)
+           (:collidable? obj2)
+           (collide? obj1 obj2))
     [(assoc obj1 :hit? true) (assoc obj2 :hit? true)]
     [obj1 obj2]))
 

    (if hit?
      (if (< fragment-size asteroid-min-size)
        nil
        (create-asteroids 3 (/ size sqrt3) position speed))
      asteroid)))

(defn resolve-all-collision [{shots :shots :as ship} asteroids]


    :direction      dir
    :rotation-speed 0

    :collidable?    true
    })
  ([{:keys [position size direction speed] :as ship}]
   (let [dir-vec (rotate-vec direction [0 1])
